Fire escape



H. J. MILLER FIRE ESCAPE May 8, 1.962

7 Sheets-Sheet 1 Filed May 13, 1960 HA/mr Ji/V/L 4 El? INVENTOR ATTORNEYS H. J. MILLER FIRE ESCAPE May 8, 1962 Filed May 15, 1960 ATTORNEYS 2 r MR) fi lm z a lh 0 v S W M m m w 1 R 1 Y B Q May 8, 1962 H. .J. MILLER 3,033,308

FIRE ESCAPE Filed May 13, 1960 7 Sheets-Sheet 3 IIIIIIIIA.

HARRY yJM/LL ER INVENTOR BY I I l 1 ATTORNEYS.

y 8, 1962 H. J. MILLER 3,033,308

FIRE ESCAPE Filed May 13, 1960 7 shreets sheet 4 HAR/FrJM/LLER INVENTOR y 8, 1962 H. J. MILLER 3,033,308

FIRE ESCAPE Filed May-13, 1960 7 Sheets-Sheet 5 INVENTOR BY v ATTORNEYS H. J. MILLER May 8, 1962 FIRE ESCAPE 7 Sheets-Sheet 6 Filed May 15, 1960 w, as 63m R 43 m m Rm m N T M L l M w 7 Y R R H 3 s \s 4 s 3 May 8, 1962 H. J. MILLER 3,033,308

FIRE ESCAPE 7 Sheets-Sheet 7 Filed May 13, 1960 HARRY c/. MIL L 5/? INVENTOR BY I I I 1 ATTORNEYS.

ilnited States Patent *Ofifice 3,033,308 Patented May 8, 1962- 3,933,398 FIRE ESCAPE Harry J. Milier, 10216 Du Vawn Place, Silver Spring, Md. Filed May 13, 1960, Ser. No. 29,077 Claims. (Cl. 182-48) This invention relates to fire escapes, and more particularly to that type of fire escape that is portable by reason of the fact that the fire escape is mounted on a wheel supported platform or truck.

One of the difiiculties encountered in rescuing people from burning buildings is that due to narrow alleys, and location of windows, it is not always possible to maneuver a conventional fire truck equipped with extension ladders commonly used in rescue work, to the necessary position for safe rescue work.

Furthermore, it is a conceded fact that for numerous reasons extension ladders are impractical for the removal of invalids, sick persons or cripples from a burning building. Therefore, it is one of the principal objects of this invention to provide a portable fire escape that can readily be adapted for use in rescuing persons trapped in the upper floors of a burning building by the persons sliding down the chutes that comprise the fire escape forming the subject matter of the present invention.

Another object of this invention is to provide a portable fire escape embodying a plurality of telescoping chute sections mounted on a self-propelling vehicle, the chutes being folded to a nested position in a longitudinal plane when out of use, and readily extended to a window or other opening for the removal or rescue of the occupants of the burning building.

Another object of this invention is to provide a portable fire escape comprising a plurality of chutes, U-shaped in cross section, the outer end sections being jointed for placement at substantially right angles to the main sections, to facilitate the removal of persons from the upper floors of a building when the vehicle is placed parallel to the building, as is frequently necessary in a narrow street or alley.

Another object of this invention is to provide a portable fire escape wherein the telescoping chutes may be extended to their limits by a single operator due to the hydraulic, air, electric or other suitable type of lifting and chute-extending mechanism.

Another object of this invention is to provide a portable fire escape comprising a plurality of interlocked extensible chutes, U-shaped in cross section and mounted on a turn table forming a part of a self propelled vehicle.

Another object of this invention is to provide a portable fire escape supporting one or more hoses for projecting a fire extinguishing agent to extinguish fire and dispel heat around or near the exit area from which persons are being removed.

Still another object of this invention is to provide a portable fire escape that can readily be adapted for mounting on the body of a conventional ladder truck in lieu of the usual ladders, eliminating the necessity of making extensive alterations in the vehicle construction in mounting the same.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawings:

FIGURE 1 is a side View of this invention showing it adapted to a self-propelled vehicle. The telescoping chutes are collapsed and ready for transporting to a needed rescue.

FIG. 2 is a side view of the telescoping chutes mounted on a self-propelled vehicle and partly extended.

FIG. 3 is a front view of the vehicle on which this invention is placed.

FIG. 4 is a top plan view of one end of one of the chutes showing it placed ready for use in a window.

FIG. 5 is an end View of FIG. 4, looking rearwardly.

FIG. 6 is a sectional view taken substantially along the line 6-6 of FIG. 2 as viewed in the direction indicated by the arrows.

FIG. 7 is an enlarged top plan view of the lower end of the supporting chute.

FIG. 8 is an enlarged top plan view of the upper end of the chute showing the hinge mechanism of its jointed outer end.

FIG. 9 is a sectional view taken substantially along the line 9-9 of FIG. 2 as viewed in the direction indicated by the arrows.

FIG. 10 is a sectional view taken substantially along the line lir -10 of FIG. 1 as viewed in the direction indicated by the arrows.

FIG. 11 is a sectional view taken substantially along the line 1111 of FIG. 2 as viewed in the direction indicated by the arrows.

FIG. 12 is a fragmentary detail of the interlocking edges of some of the chute sections, the detail being shown in section for clarity.

FIG. 13 is an enlarged view of the latch.

FIG. 14 is a sectional view taken substantially along the line 14-14 of FIG. 1 as viewed in the direction indicated by the arrows.

FIG. 15 is an enlarged side view of a portion of the chutes showing them in a telescoped position.

FIG. 16 is a sectional view taken substantially along the line 16-16 of FIG. 15 as viewed in the direction indicated by the arrows.

FIG. 17 is a perspective view of a portion of two of the hinge connections of this invention.

FIG. 18 is a sectional view taken substantially along the line 18-18 of FIG. 1 as viewed in the direction ine dicated by the arrows.

FIG. 19 is a sectional view taken substantially along the line 19-49 of FIG. 2 as viewed in the direction indicated by the arrows.

FIG. 20 is a sectional view taken substantially along the line lit-20 of FIG. 2 as viewed in the direction indicated by the arrows.

FIG. 21 is a semi-diagrammatic drawing of the hydraulic cylinder, hydraulic hose lines, control valves and all other major components of the necessary chute operating mechanism.

FIG. 22 is a diagrammatic drawing of a typical hydraulic circuit as used in this invention.

FIG. 23 is a plan view of the collapsible rescue net forming a part of the invention.

Similar reference characters refer to similar parts throughout the several views of the drawings.

Having reference now to the drawings in detail, and in particular to FIG. 1, there is generally indicated by the reference character 25 a self-propelled vehicle having a platform 26 on which is rotatably mounted on ball bearings 77' a turntable 27 having a pair of spaced stanchions 2% secured thereto, as well as a hinge type of support 29 for one end of a hydraulic cylinder 30 that telescopes the chute assembly 31,as will be hereinafter described. A hydraulic spring loaded hose reel 32 is also mounted on the turntable, as well as a pair of spaced vertically mounted hydraulic cylinders 33 that lift and lower the aforesaid chute assembly 31.

The chute assembly 31 comprises a plurality of telescoping sectional members 34 which are U-shaped, in cross section with their longitudinal marginal edges rolled outwardly providing open telescoping tubes or hand rails 39, as illustrated by FIG. 16 of the drawings. In the illustrated embodiment, the chute assembly 31 is in six sections, although in actual practice the chute may embody any desired number of sections depending upon the maximum height above the ground required for this type of rescue operation.

The aforesaid six sections of the chute assembly 31 embody a supporting section 34 in which are telescoped three internested identical sections 35, 36 and 37, and an intermediate section 38. A U-shaped channel 38' is secured laterally to the underside of the section 38, as clearly shown in FIG. 11 of the drawings.

The forward edge of internested section 35, both forward and rearward edges of internested sections 36 and 37, and the rearward edge of supporting section 34 are bent upon themselves as at 36' so that when the sections are extended and the ends are brought together the ends of the sections automatically interlock in the manner clearly shown in FIG. 12 of the drawings. The purpose of the interlocking ends is to cause each of the sections of the chute to be drawn outwardly when the adjacent internested section 35 is pulled to the limit of its outward movement. The marginal longitudinal edges 39 which are herein illustrated and form an important part of the invention, are created by rolling the longitudinal edges of said chutes outwardly as best shown in FIG. 16 of the drawings. One of said sections supports one member of hinge 40 which is secured thereto, while the other portion of the hinge is secured in like manner to the lower end 41 of hand rail 42 of the intermediate section 38, as shown by FIGURE 15.

The swingable end chute 43 has its inner end fiexibly secured to the outer end of the stated intermediate chute 38 by means of a flexible, fireproof semi-cylindrical bellows-like member or elbow 44, as clearly illustrated by FIGS. 1, 2, 4, and 8 of the drawings. Thus it will be obvious that the elbow will permit of ready adjustment of the chute to adapt the chute for positioning for rescuing persons from unusual locations.

An arm 45, of triangular shape as viewed from above, is secured at one end to a lateral side of the end chute 43 and extends outwardly therefrom and has an elongate opening 46 therein and extending longitudinally thereof, in which is disposed a pin 47 secured to the outer end of piston rod 48 of the hydraulic cylinder 49 that is secured to the left side of the intermediate section 38 when it is viewed rearwardly from the vehicle 25.

A guide rod 50 is secured at both ends to the opposite side of the chute 43 from that of arm 45. This rod slidably supports the hinged end member 51 of arm 52 (see FIG. 8), that, in turn, is pivotally secured to a forwardly extended arm 53 that is rigidly secured at its rear end to the outer end of intermediate chute 38. The aforesaid mechanism, characterized by reference numerals 45 to and including 53, is located below the hand rails which are similar to and in line with those of the intermediate section 38 and noted by the reference character 42.

Referring again to FIGS. 1 and 2, it will be seen that the entire embodiment of the above described chute 31 is swingably supported by the stanchions 28, and that the pivoted end of the supporting section 34 terminates in an upwardly curved portion as at 54.

As better shown by FIG. 19, the previously referred to hydraulic cylinder 30 contains a hollow piston 55 which is keyed to the cylinder, and a plurality of tubular extension members nested within the stated piston. In the embodiment illustrated by the drawings, only two of these tubular extension members are illustrated, the first member being designated by the reference character 56, which is keyed within the piston 55 for longitudinal sliding movement, while a second tubular member 57 is keyed within tubular member 56.

The outermost end 58 of the tubular extension member 57 is T-shaped, with an opening through the same and at right angles to said tubular extension member 57. A removable pin 59 detachably secures member 57 to the lower end of the intermediate section 38 of chute 31 by passing through openings in a yoke 60 which is firmly secured to the aforesaid chute section 38, as well as through aligned openings in both the U-shaped channel 38 and the aforesaid T-shaped end 58 of member 57, thus providing a detachable and vertically swingable connection between the intermediate chute and the hydraulic cylinder 30. Obviously the openings in the yoke 60 are also in alignment with the openings in the U-shaped channel 38, since it is necessary that the yoke 60 be located in line with the necessary opening in the U-shaped channel member 33' on the intermediate section 38 as can be understood by examination of FIGS. 1, 2 and 11 of the drawings.

The yoke 63 has an inverted U-shaped opening 60 at its lowest extremity directly under the vertical axis of the U-shaped channel 38, in which the upper end of rod 61 of the hydraulic cylinder 62 is pivotally mounted by means of a removable pin 63, as clearly shown in FIG. 11 of the drawings. The hydraulic cylinder 62 is obviously located on the rear of the previously stated flat bed 26 of the vehicle. The purpose of the cylinder 62 will be described in detail hereinafter, in that part of the specification dealing with the operation of this portable fire escape.

It will be noted that the hydraulic cylinder 35} is supported by a standard 63' having a yoke 64-, since the cylinder is obviously of such length as to require this additional support.

As has been previously stated, the yoke 60 is secured to the lower end of the intermediate section 38 of the telescoping chutes. A spring loaded latch 65 is located on each side of the aforesaid intermediate section 38 of the chute, and has its male member 66 secured to the side of the yoke 69, While the keeper 67 is attached to the rearward end of internested section 35 for the obvious necessity of securing the two sections of the chute together when it is ready for use.

A tension cable 68 is located on each side of the chute, one end of each cable being secured to the front end of the swingable end chute 43, while the other end is secured to a spring loaded drum 69 which is mounted on a frame 70 attached to the outside of the front end of the supporting section 34 of the chute, as better shown by FIG. 7. The cable passes over an idler pulley 71 which is located just above each drum 69, and then continues along the sides of the chutes directly under the hand rails 39 to the aforesaid point of securement. The idler pulley 71 is of course also attached to the same frame that supports the drum 69, since the chute itself is obviously of too thin a material for direct attachment of these parts.

It has been previously stated that a hydraulic hose reel 32 is located on the turntable 27, although its purpose was not given, and that a hydraulic cylinder 49 is secured to the left side of the intermediate section 38 for swinging the end chute 43 into place. Obviously the hydraulic cylinder 49 must be supplied with hydraulic fluid, and since the distance from the cylinder 49 to the turntable 27 varies by reason of the telescoping chute 31, the hydraulic hose 72 is provided, and has one end connected to the cylinder 49 while the other end is coiled around the spring loaded hose reel 32 and then connected with a hose that leads to the control box 73 located at the forward end of the vehicle 25, as will be hereinafter described.

A pair of idler pulleys 74 are mounted on the same side of the intermediate chute 38 as the aforesaid hydraulic cylinder 43 and near the forward end of the intermediate section in order to hold the hose 72 in the desired position in relation to the side of the intermediate chute 38 as shown in FIGS. 1 and 2 of the drawings.

Before describing the actual operation of this fire escape, it will first be necessary to understand its bydraulic circuits, since there are four identical circuits, all being supplied by a single tank 81 containing hydraulic fluid pumped by a single pump 8%, as clearly shown in FIG. 21 of the drawings.

FIG. 22 of the drawings illustrates a typical basic hydraulic circuit which embodies a hydraulic cylinder 75, a manually operated control valve 76, an unloading valve 77, a back pressure valve 78, a relief valve 79, a pump 86 and a tank 81. Pipe lines connect the component parts of the circuit as stated. The pipe lines have not been given reference numerals, since the circuit will be clearly understood by those experienced in mechanics, upon examination of FIG. 2.

Referring again to FIG. 21, it will be seen that with the exception of the hydraulic cylinders and the manually operated control valves, all other parts of the hydraulic circuit have the'same reference characters as the equivalent parts in the above described FIG. 22 of the drawings, since they operate in an identical manner and are connected in the circuit the same way.

With a view for convenience in operating the apparatus in the dark, a conventional electric flood lamp 26' is mounted at the rear end of the bed 26, the lamp 26' being of the adjustable type for projecting light rays to the desired location.

The construction of this portable fire escape and its hydraulic circuits have now been described, and it only remains to set forth how it is operated in order to rescue persons from a building.

It is assumed that the vehicle 25 has been driven to the building B (FIGS. 4 and 5) from which rescue is desired, and that it has arrived with the telescoping chutes in a retracted and folded position as indicated in FIG. 1 of the drawings.

The vehicle is made stable by the use of pneumatically operated outriggers or jacks 1M and 101 at the front and rear ends respectively of the vehicle.

The intermediate section 33 of the chute is now swung down in line with the supporting section 34 of the chute, the swinging being accomplished about the axis of the hinges 40 that connect the intermediate section 38 with the aforesaid sup-porting section 34. The actual swinging of intermediate section 38 is of course accomplished by the downward action of the rod 61 of hydraulic cylinder 62 since the upper end of the rod 61 is hingedly secured in the bottom of yoke 60 by means of the removable pin 63, since the stated yoke is of course firmly fixed to the front end of the aforesaid intermediate section 38. The movement of rod 61 in the hydraulic cylinder 62 is controlled by means of the manually operated valve 82, since both the valve 82 and cylinder 63 are part of the same hydraulic circuit, a typical one of which has been previously described in this specification.

The intermediate section 38 is now firmly secured to one end of the outermost section 35 by means of a latch 45 located on each side of the above mentioned chute, and a manually operated control valve 83 is then opened causing the piston 55 in hydraulic cylinder 30 to move outwardly towards the rear of the vehicle, and this action will of course result in the extension of the arms or tubular extension members 56 and 57, nested or telesccped within each other, in such a manner that the opening in the outer end of the second tubular extension member is in line with the opening in the front end of the U-shaped channel 33 and the yoke 66. A removable pin :39 is now inserted in the aforesaid openings and in the outer end 53 of the aforesaid second tubular extension member 57, as clearly shown in FIGS. 2 and 17 of the drawings.

Removable pin 63 is now removed from the upper end of rod 61 and the lower end of yoke 60. The control valve 83 is opened still further and at the same time another manually operated control valve, designated by the reference character 84 in FTGS. 3 and 21, is opened to raise the chute to the desired height necessary for the rescue, by reason of the extension of the piston rods 85 in hydraulic cylinders 33 since the stated piston rods 85 are swingably mounted in the cradle 86 which is secured to and supports the supporting section 34 of the chute by means of a pin 87 on each side of the cradle 86.

It is now obvious from the above description and examination of FIGS. 2 and 21 of the drawings that the extending and raising of the chute is an operation performed simultaneously by the aforesaid opening of the valve 84 so that the chutes extend both upwardly and outwardly at the same time to the desired place of rescue. The manually operated valve 88 is now opened to permit hydraulic fluid to enter cylinder 49 that is secured on one side and at the outer end of the intermediate section 38 of the chutes. The piston rod 43 of the stated cylinder is both pivotally and slidably adapted to the swingably mounted end chute 43 in a manner previously described. The top 89 or outer end of end chute 33 is now placed in line with the edge of the door or opening from which rescue is to be effected by means of the action of the aforesaid piston 48 on the above described mechanism when the valve 88 is opened, since the end chute 43 is actually pivoted about a hinge pin 53 although the lower end of the chute is connected to the upper end of the intermediate section 38 by means of the semi-cylindrical bellows-like member 44 as previously described, inorder that a person may readily slide from the end chute 43 into the intermediate section 38 when the end chute is set at a desired angle in relation to the intermediate section by the obvious action of the previously described mechanism, upon operation of the manually controlled valve 88. It is also clear from examination of FIGS. 4 and 5 that the end chute 43 may be swung laterally within certain limits and with respect to the intermediate section as described, although the end chute is shown as pivoted to the right of the intermediate section, in the accompanying drawings.

The electric switch 90 is now manually closed thus permitting the completion of the electric circuit that will result in the electric motor 91 rotating the turntable 27 through reduction gear 92 and ring gear 93 which is secured to the underside of the stated turntable by means of a shaft 94 that is shown only in FIG. 21 of the draw ings. The chute section at the outer free end of the main or supporting chute section 31 by which means rescue is effected, is now brought into contact with the ledge of the window or door, it being realized that some juggling of the control valves 83, 84 and 88 may be necessary in order to locate the end chute in the necessary place for rescue.

It should be noted that the hose 72 actually contains two separate hoses 95 and 96, see FIG. 5, since the hydraulic cylinder 49 of course has a fluid inlet and outlet at each end thereof. It should also be noted that flexible hose must be used to connect the hydraulic cylinders 30 and 33 with the unloading valves 77, back pres sure valves 78 and manually operated control valves 83 and 84. Flexible hose must also connect the hoses 95 and 96 with valves 77, 78 and 83, since part of the mechanism that comprises this invention is on the turntable 27 and part is fixed on the body of the vehicle 25.

It is obvious from examination of FIGS. 2, l2, l5 and 16 that when the internested section 35 of the chute is extended as previously described, the internested sections 36 and 37 will become extended due to the U-shaped inturned ends 36' of the sections becoming interlocked as the adjacent ends meet, as clearly shown in FTG. 12 of the drawings. The illustration in FIG. 12 is typical of the interlocking ends, although one member in this figure is characterized as the interncsted section 35 and the other is the internested section 36, and the identical construction applies to the ends of the internested section 37 and the rear end of the. supporting section 34.-

A person sliding through the inclined chute upon being rescued will enter the upturned end 54 of section 34. This upturned end will act to direct the person to land in a collapsible net 97 such as shown in FIG. 22 and which is supported adjacent to the outlet or laterally extended end 54 of the chute as shown by FIG. 1 of the drawings.

The net 97 is preferably of the foldable or collapsible type supported on the legs 93 which are pivotally connected to the frame of the net to be folded into a small and compact article to conserve storage space on the vehicle. The legs 98 are formed with extensions 99 that are rcmovably held in sockets 102 formed in the upper surface of the bed 26, as better shown by FIG. 1 of the drawings, when the net is opened for mounting.

After a rescue has been eitected, the end chute 43 is swung in line with the intermediate section 38 by means of the manually operated control valve 88, the entire chute 31 and its associated sections are swung back in line with the vehicle 25 by means controlled by the electric switch 90, and the chute is then telescoped by operation of the valve 33. When this operation is completed the chute is lowered by means controlled by the electric switch 99, and the chute is then telescoped by operation of the valve 83. When this operation is completed the chute is lowered by means of the operation of valve 84 until the hydraulic cylinder rests in the yoke 64. The pin 63 is then removed from the device and the manually operated control valve 82 is operated so that the outer end of rod 61 of hydraulic cylinder 62 is within the lower inverted U-shaped end of yoke 66 and the removable pin 63 is then replaced and the internested section disconnected from the intermediate section 38 upon opening of the spring loaded latches 65, one of which is on each side of the chute. The control valve 82 is now operated so that the hydraulic fiuid in the cylinder 63 will force its piston and attached rod 61 upwardly, thereby swinging the intermediate section 38 and its attached end chute 43 upwardly and rearwardly to the position shown in FIG. 1 of the drawings, by reason of the fact that the intermediate section 38 is secured to the internested section 35 by means of hinges 40, as previously described.

From the foregoing it will now be seen that there is herein provided a fire escape which accomplishes all of the objects of this invention, and others, including many advantages of great practical utility and commercial importauce.

While I have shown and described my invention as primarily designed for use as a mobile fire escape, it is to be understood that the structure may be effectively employed as an apparatus for unloading materials from warehouses, steamships or the like without departing from the spirit of the invention.

As many embodiments may be made of this inventive conce t, and as many modifications may be made in the embodiment hereinbefore shown and described, it will be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

1 claim:

1. In a mobile escape apparatus for rescuing a human or other body from a burning structure, the new combination with a mobile support body, of an open trough chute assembly of elongate sections, the assembly comprising a lower support chute section, means pivotally supporting said lower section for vertical swinging on a horizontal axis, an outer chute section, means operatively coupling said lower and outer chute sections for limited relative rectilinear sliding movement for extending and retracting the outer chute section relative to the support section, an intermediate chute section, hinge means between an end of the latter section and the outer end of the outer chute section whereby the intermediate chute section may be swung from a position of alignment with the outer section to a substantially superposed relationship with the support and outer chute sections when the outer section is retracted, means for locking the intermediate and outer chute sections together when the same are aligned, a first power means including a reciprocable member beneath and movable longitudinally of the lower chute section, a second power means adjacent to said hinge means, means operatively and detachably coupling said second power means with said intermediate section for efiecting the said swinging of the latter, means for operatively connecting said reciprocable member of the first power means with said outer chute section for extending the latter chute section and the intermediate chute section after the second power means is uncoupled from the intermediate section and the latter is locked to the outer section, power means connected with and for effecting said vertical swinging about said horizontal axis of the lower chute section together with the other sections, and the lower end of said lower chute section being open for discharge of the rescued body from the chute assembly.

2. The invention according to claim 1, wherein the said second power means includes a normally upwardly directed reciprocable rod, and said means operntively and detachably coupling the second power means with said intermediate section comprises a yoke secure to said intermediate section and a removable pin member pivotally connecting the upper end of said rod to the yoke.

3. The invention according to claim 1, wherein said second power means includes a normally upwardly directed reciprocable rod and the said means operatively and detachably coupling the second power means with said intermediate section comprises a yoke secured to the intermediate section and having a part extending away from the underside of the intermediate section and a removable pivot pin coupling the upper end of said rod with said yoke part, and the said means for operatively connecting the said reciprocable member of the first power means with the outer chute section after the latter section is locked to the intermediate section includ ing a removable pin between the said yoke part and the last mentioned member.

4. The invention according to claim 1, with a swingable end chute section, a flexible bellows-like semi-cylindrical body connecting an end of the end chute section with the outer end of the intermediate section, a power unit supported on one lateral side of the intermediate section adjacent to said outer end thereof, means operatrvely coupling said power unit with the adjacent lateral side of the end section for applying a push or pull to the end section by the power unit, and an articulated supporting arm upon the opposite lateral sides of the intermediate section and the end section and bridging the connecting bellows body, the said arm having one elongate part secured at one end to the intermediate section and a second elongate part pivotally and slidably coupled at one end to the end section and said arm parts being pivotally connected together at their other ends.

5. The invention according to claim 4, wherein the said means operatively coupling the power unit with the adjacent end section comprises a reciprocable rod forming an element of the power unit and movable longitudinally of the intermediate section, an arm secured at one end to the said adjacent lateral side of and extending outwardly from the end section, the arm having therein an opening extending longitudinally thereof, and a coupling pin carried by the last-mentioned rod and having sliding engagement in said opening.

References Cited in the tile of this patent UNITED STATES PATENT S 139,416 OBrien May 27, 1873 164,278 Dunbar June 8, 1875 522,759 Landis July 10, 1894 1,364,581 Ramsey Jan. 4, 1921 1,581,660 Rosgaard Apr. 20, 1926 2,713,929 Castendyck July 26, 1955 2,880,977 Maxon Apr. 7, 1959 

